This invention relates to a front wheel transaxle for an all-wheel drive motor vehicle and more particularly to an improved arrangement therefore wherein two subassemblies are provided that upon incorporation in the transaxle assembly obviate the mixing of lubricants.
The U.S. Pat. Nos. 4,582,160 and 4,601,359 together with the European Patent Office publication (EPO 198 812 A3) are examples of prior art front wheel drive transaxles adapted for four-wheel drive vehicles. In such transaxles the axle differential, including its outer housing, often comprises the housing of the shiftable transmission, on the one hand, and the angle drive, including its housing, on the other hand. The axle differential with its housing and the shiftable transmission with its housing are designed to be made as separate subassemblies in different plants. This necessitates that each subassembly be tested with its compatible lubricant introduced prior to its assembly into the transaxle. Such testing previously involved considerable difficulty because of the lack of separate seals for each subassembly. Further, a particular kind of lubricant is usually required for both the differential and the shiftable transmission while a different kind of lubricant is required for the angle drive mechanism. It is also a concern to insure that in the event of damage or failure of one of the assembly seals a mixing of the two different lubricants be prevented.